Description: Floating plants
with thick, glossy leaves, inflated
petioles and spikes of lavender flowers.
Native Range: Brazil, South America.
Range indicates presence in at least one
site within a drainage (USGS Hydrologic Unit 8), but
does not necessarily imply occurrence throughout.
Nonindigenous Occurrences: Established and self sustaining in over 150
U.S. drainage basins in 10 states. Recently found persisting as far north as
the Lower Cheaspeake [P. Baldwin s.n. (WILLI)] and Tidewater regions
of coastal Virginia (pers. comm. L. Swanson, VA Coop. Ext. Agency). Weedy
in North Carolina north and inland to the Upper Tar and Neuse River drainages
(pers. comm. Stratford Kay, NC State Univ.). Intermittently distributed in Georgia
and Mississippi. Often extemely problematic in Florida, Alabama,
Louisiana and eastern Texas. Also established in California
and Hawaii.
Waif or nonpermanent populations have been reported from more temperate states
including New Jersey,
Kentucky, Tennessee,
Missouri and Arkansas
where plants apparently escape summertime cultivation to grow as annuals, but
do not persist vegetatively through the winter. Water-hyacinth is stocked annually
in private fish ponds throughout southern Arizona
and in Delaware at old mill ponds.
It has been reported from the Great Cypress Swamp, southern Delaware
and from isolated, natural locals in New
Jersey. Water-hyacinth is capable of reproducing by seed. However,
it is not known if recurrence by seed plays a role in the waif populations of
these temperate states. October 2002 First
recorded for the state of Illinois in the Fox River Chain O' Lakes in the Upper
Fox drainage where several hundred plants were documented, although none are
expected to overwinter (Marencik s.n. FLAS; pers. comm. J. Marencik,
Lake Co. Health Dept, CNC). December 2002 Reported
for Maryland in
1998 at a pond near Lake Shore, in the Severn Drainage; this site will be checked
during the 2003 growing season to see if the plants have persisited (pers. comm.
W. Sipple, EPA). October 2003 Several
plants were reported
from the Ebbing Air National Guard Base in Fort Smith,
Arkansas, where plants were found
growing along a drainage
ditch located just below a spillway
for a small, recreational, fish stocked pond. All of the plants were manually
removed and the site will be monitored for future occurrences (pers. comm.
S. Hardcastle and J. Christensen, AR Air National Guard).
Author: C.C. Jacono and M.M. Richerson
Revision Date: 22 Oct. 2003
